Insights Discovered From Comparative Retrievals of Substellar Objects

Subdwarfs, objects that have metallicities significantly lower than that of the Sun, provide insight into understanding how metallicity affects observable features of low-mass stars and brown dwarfs. Currently, substellar subdwarfs are thought to have cloudless atmospheres due to reduced condensate opacities from their low-metallicities. In this talk, I aim to explore the nature of clouds in subdwarfs using the spectral inversion modeling technique of atmospheric retrievals. With this technique, we derive a Pressure-Temperature (PT) profile to describe the atmospheric structure of a given target. Using the retrieval code Brewster, I compare a sample of field sources of similar temperature or spectral type to SDSS J1416A — an L dwarf primary in a widely-separated subdwarf binary system— to determine how the PT profile of these objects compares and what may drive the differences we see in their spectra. I will present the initial findings of this work which shows the need for longer wavelength data to fully constrain the cloud properties of substellar objects.